This invention generally relates to a surgical instrument, and more particularly to an instrument for applying a fastener to tissue of a patient.
Gastroesophageal reflux disease or persistent heartburn is caused by an improper relaxation of the lower esophageal sphincter, allowing acidic stomach contents to travel into the esophagus. If left untreated, chronic reflux may cause esophageal stricture, bleeding ulcers, perforation, and scarring. Continued reflux may lead to Barrett's esophagus, involving changes in the esophageal cells and possibly leading to cancer. Antacids and proton pump inhibitors are initially used to treat this condition. If these treatments are unsuccessful, surgical intervention is often recommended.
One interventional surgical method is known as Nissen fundoplication. This procedure involves wrapping a fundus of the stomach around the lower end of the esophagus and fastening it in place to make the lower esophageal sphincter less compliant. Traditionally, this procedure was accomplished by open surgery using sutures to secure the plicated fundus of the stomach around the esophagus without penetrating the stomach. More recently, laparoscopic Nissen procedures have been used. In some laparoscopic procedures, surgical fasteners are used with an endoscopic applicator. Several different fastener designs have been developed. Some of these designs include a two piece fastener. A first of these pieces, a male component, includes a base having two straight elongate needles extending perpendicularly outward from the base generally parallel to each other. A second piece, a female component, includes a receiver element having openings positioned for receiving the needles of the first piece and a lock for holding the needles in place once received in the openings. In use, tissue is gathered, the needles of the first piece are pushed through the gathered tissue and the openings of the second piece to hold the tissue and fastener in place.
Various applicators are used to apply the fastener to the tissue. One applicator includes an elongate shaft having two jaws pivotally attached to its end. The jaws include receptacles for holding the first and second pieces of the fastener. The jaws push the needles of the first piece through the gathered tissue and the openings of the second piece to hold the tissue and fastener in place. As will be appreciated by those skilled in the art, because both jaws are pivotally attached to the shaft, both pieces of the fastener sweep through arcs as the jaws pivot to pierce the tissue and push the needles into the corresponding openings. As a result of the fastener pieces sweeping through arcs, both fastener pieces move relative to the tissue, making precise placement of the fastener in the tissue difficult. Even when the needles engage the tissue, the folded tissue can move relative to the female fastener component before the fastener components are fastened together. Thus, there is a need for an applicator that reduces the opportunity for the tissue to move as the fastener is applied.